// Copyright 2013 Petar Maymounkov
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
	"strconv"
	"sync"
)

type Counter struct {
	sync.Mutex
	counters map[string]*map[string]int
}

func (c *Counter) Init() {
	c.counters = make(map[string]*map[string]int)
}

func (c *Counter) Label(counterName string, itemName string) string {
	c.Lock()
	defer c.Unlock()
	d, ok := c.counters[counterName]
	if !ok {
		p := make(map[string]int)
		d = &p
		c.counters[counterName] = d
	}
	g, ok := (*d)[itemName]
	if !ok {
		g = len(*d) + 1
		(*d)[itemName] = g
	}
	return strconv.Itoa(g)
}
